1. Field of the Invention
The present invention relates to an image display device and a lighting device for providing uniform light in the display device, and more particularly, to a light guide plate having a stepped edge and a backlight assembly having the light guide plate, and also to a liquid crystal display device employing the backlight assembly.
2. Description of the Related Art
Image display devices such as liquid crystal display (LCD) devices basically have a light assembly for providing light, a display assembly for processing image data and displaying images thereon, and various types of optical means for converting the light from the light assembly into light more appropriate for the display assembly. Such optical means generally include a light guide plate that guides the light from the light assembly to provide the display assembly with light having uniform distribution, and one or more optical sheets that enhance the luminance at the display assembly by adjusting paths of the light provided from the light assembly through the light guide plate.
There have been developments in reducing the size of LCD devices while improving their functions and performance. One of such developments has been made on fabrication of the light guide plates. Various types of light guide plates have been introduced for a light assembly providing the light with uniform luminance distribution in an LCD device. Since a light guide plate and a light assembly in an LCD device have a close relationship in the aspects of their structure and function, the light assembly would need to be modified in association with the light guide plate when the light guide plate is newly designed to provide better quality light to a display unit.
However, there have been difficulties in reducing the size of LCD devices by modifying the light guide plates and the light assemblies, and drawbacks exist in the conventional light guide plates and light assemblies developed for the purpose of reducing the size of the LCD devices. Also, there has been a demand of display devices with a compact and slim size. Especially, for the portable electronic products with display features, the size of products is an important factor to attract the customers and lead to a success in the market.
Therefore, a need exists for a display device having a reduced overall size, especially a narrow bezel, and a light assembly with light guide plate having structure contributing to the reduction of the device size.